D1 Dopamine Receptor Mediation of Social and Nonsocial Emotional Reactivity in Mice: Effects of Housing and Strain Difference in Motor Activity

• Published in: Behavioral neuroscience 1997-04, Vol.111 (2), p.424-434
• Main Authors: Gendreau, Paul L, Petitto, John M, Gariépy, Jean-Louis, Lewis, Mark H
• Format: Article
• Language: English
• Subjects: Acoustic Reflex; Activity Level; Animal; Animal Environments; Animal Rearing; Animal Strain Differences; Animals; Arousal - drug effects; Arousal - physiology; Behavioral psychophysiology; Benzazepines - pharmacology; Biological and medical sciences; Brain; Dopamine; Dopamine Agonists - pharmacology; Emotions - drug effects; Emotions - physiology; Female; Fundamental and applied biological sciences. Psychology; Male; Mice; Mice, Inbred A; Mice, Inbred C57BL; Motor Activity - drug effects; Motor Activity - physiology; Neurology; Neurotransmission and behavior; Phenanthridines - pharmacology; Psychology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Receptors, Dopamine D1 - drug effects; Receptors, Dopamine D1 - physiology; Reflex, Startle - drug effects; Reflex, Startle - physiology; Rodents; Social Behavior; Social Isolation; Species Specificity; Startle Reflex; Sulpiride - pharmacology
• ISSN: 0735-7044; 1939-0084
• DOI: 10.1037/0735-7044.111.2.424

The study examined the effects of isolation housing and the role of D 1 dopamine receptors on isolation-induced social and nonsocial (acoustic startle) reactivity in mice high (C57BL/6) and low (A) in motor activity. Isolation housing had no effect on acoustic startle but increased strain-specific forms of social reactivity. The D 1 agonist dihydrexidine (DHX) increased acoustic startle in isolated mice of both strains, but this effect was more pronounced in C57BL/6 mice. In this strain, DHX and the D 1 agonist SKF-81297 increased locomotor forms of social reactivity (e.g., escape, jump), whereas the D 1 antagonist SCH-23390 increased stationary reactivity (e.g., freezing). In A mice, DHX and SKF-81297 increased and decreased stationary reactivity, respectively, whereas SCH-23390 had no effect on these behaviors. Administration of SKF-81297 after pretreatment with SCH-23390 or the D 2 antagonist sulpiride confirmed the importance of D 1 receptors in mediating specific forms of social reactivity in C57BL/6 mice. These results suggest an important relationship between social reactivity and motor activity and an important, albeit strain-dependent, role for D 1 receptors in mediating specific emotional behaviors.